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Hyperspectral Imagery Target Detection Using Improved Anomaly Detection And Signature Matching Methods, Timothy E. Smetek Jun 2007

Hyperspectral Imagery Target Detection Using Improved Anomaly Detection And Signature Matching Methods, Timothy E. Smetek

Theses and Dissertations

This research extends the field of hyperspectral target detection by developing autonomous anomaly detection and signature matching methodologies that reduce false alarms relative to existing benchmark detectors, and are practical for use in an operational environment. The proposed anomaly detection methodology adapts multivariate outlier detection algorithms for use with hyperspectral datasets containing tens of thousands of non-homogeneous, high-dimensional spectral signatures. In so doing, the limitations of existing, non-robust, anomaly detectors are identified, an autonomous clustering methodology is developed to divide an image into homogeneous background materials, and competing multivariate outlier detection methods are evaluated for their ability to uncover hyperspectral …


Point Spread Function Characterization Of A Radially Displaced Scatterer Using Circular Synthetic Aperture Radar, Uttam K. Majumder Mar 2007

Point Spread Function Characterization Of A Radially Displaced Scatterer Using Circular Synthetic Aperture Radar, Uttam K. Majumder

Theses and Dissertations

This research effort investigated characterizing the point spread function (PSF) behavior of radially displaced point scatterers using circular synthetic aperture radar (CSAR). Thus far, research has been conducted to understand PSF of a scatterer located at the imaging scene center. An analytic closed-form solution has been derived assuming the scatterer is located at the origin of the CSAR imaging geometry. However, it is difficult to derive an analytic PSF solution for a scatterer that is radially displaced from the imaging scene center. Using the back projection image formation algorithm, PSF responses are generated at various point target locations. Consistent with …